1. Field of the Invention
The present invention relates to a reverse side printing device employing a sheet feed cylinder and provided in a sheet-fed double-sided printing machine.
2. Background of the Invention
In a conventional sheet-fed double-sided printing machine, a sheet is conveyed between an obverse (front) side printing blanket and a reverse side printing blanket so that both the obverse and reverse sides of the sheet are printed at the same time. Since the printing machine is used exclusively for printing both the sides of the sheet, the printer is not capable of printing only one side of the sheet. Since the blankets are rubber cylinders, dragged printing is caused so that the sharpness of a printed net pattern or a printed point pattern is low.
In another conventional sheet-fed double-sided printing machine, the obverse side of a sheet is first printed, and the sheet is then turned over by an inversion mechanism to print the reverse side of the sheet. However, the switching operation of the inversion mechanism is inconvenient, and the accuracy of the printing is lower than a sheet-fed single-sided printing machine.